修复截取图片，重新编译时gyp报错。

[gxdyxh]

PS D:\desktop\node-images-master> node-gyp configure gyp info it worked if it ends with ok gyp info using node-gyp@6.0.1 gyp info using node@10.16.0 | win32 | x64 gyp info find Python using Python version 2.7.17 found at "E:\tool\Python27\python.exe" gyp info find VS using VS2019 (16.3.29418.71) found at: gyp info find VS "d:\Microsoft Visual Studio\2019\Community" gyp info find VS run with --verbose for detailed information gyp info spawn E:\tool\Python27\python.exe gyp info spawn args [ 'C:\Users\gqz\AppData\Roaming\npm\node_modules\node-gyp\gyp\gyp_main.py', gyp info spawn args 'binding.gyp', gyp info spawn args '-f', gyp info spawn args 'msvs', gyp info spawn args '-I', gyp info spawn args 'D:\desktop\node-images-master\build\config.gypi', gyp info spawn args '-I', gyp info spawn args 'C:\Users\gqz\AppData\Roaming\npm\node_modules\node-gyp\addon.gypi', gyp info spawn args '-I', gyp info spawn args 'C:\Users\gqz\AppData\Local\node-gyp\Cache\10.16.0\include\node\common.gypi', gyp info spawn args '-Dlibrary=shared_library', gyp info spawn args '-Dvisibility=default', gyp info spawn args '-Dnode_root_dir=C:\Users\gqz\AppData\Local\node-gyp\Cache\10.16.0', gyp info spawn args '-Dnode_gyp_dir=C:\Users\gqz\AppData\Roaming\npm\node_modules\node-gyp', gyp info spawn args '-Dnode_lib_file=C:\\Users\\gqz\\AppData\\Local\\node-gyp\\Cache\\10.16.0\\<(target_arch)\\node.lib', gyp info spawn args '-Dmodule_root_dir=D:\desktop\node-images-master', gyp info spawn args '-Dnode_engine=v8', gyp info spawn args '--depth=.', gyp info spawn args '--no-parallel', gyp info spawn args '--generator-output', gyp info spawn args 'D:\desktop\node-images-master\build', gyp info spawn args '-Goutput_dir=.' ] gyp: gyp\gyp\libpng.gyp not found (cwd: D:\desktop\node-images-master) while loading dependencies of binding.gyp while trying to load binding.gyp gyp ERR! configure error gyp ERR! stack Error: gyp failed with exit code: 1 gyp ERR! stack at ChildProcess.onCpExit (C:\Users\gqz\AppData\Roaming\npm\node_modules\node-gyp\lib\configure.js:351:16) gyp ERR! stack at ChildProcess.emit (events.js:198:13) gyp ERR! stack at Process.ChildProcess._handle.onexit (internal/child_process.js:248:12) gyp ERR! System Windows_NT 10.0.18362 gyp ERR! command "E:\tool\nodejs\node.exe" "C:\Users\gqz\AppData\Roaming\npm\node_modules\node-gyp\bin\node-gyp.js" "configure" gyp ERR! cwd D:\desktop\node-images-master gyp ERR! node -v v10.16.0 gyp ERR! node-gyp -v v6.0.1 gyp ERR! not ok

[gxdyxh]

抱歉没有注意到有个文件夹，需要单独下载。